8/12/2008 -- The good news, at least from Cisco Systems Inc.'s perspective, is that a recent survey of service provider customers has named it one of the top five voice-over-IP (VoIP) vendors in the industry, along with rival Alcatel-Lucent and VoIP specialists Acme Packet and Sonus.

The survey, conducted by market watcher Infonetics Research, found that Cisco is also tops in brand recognition.

The bad news, again from Cisco's perspective, is that survey respondents familiar with the ins and outs of the different vendor offerings rated Sonus as tops in technology, product roadmap, security, management and price-to-performance.

According to Infonetics, carriers cited three over-riding technical challenges associated with their deployments: competition, migration to IMS, and reductions in capital expenditures (or capex).

"Service providers are operating in a capped capex environment now -- meaning, generally they purchase equipment only when they need it," said Stéphane Téral, principal analyst at Infonetics, in a statement. "There are some areas in which most carriers are increasing their capex, though: growth areas tied to additional revenue, such as VoIP."

Right now, VoIP is still a work in progress. The top retail VoIP service for business and residential customers alike is voice-over-broadband, for one thing. In addition, fully 40 percent of respondents won't complete their migrations to Class 4/tandem switching until after 2009. This suggests "they have enough capacity to handle international voice traffic growth," according to Infonetics.

While Cisco was tops in brand recognition, and Sonus was tops in just about everything else, respondents also singled out specialist Acme Packet. More than half (55 percent) of service providers are currently using that vendor's session border controllers. --Stephen Swoyer